The invention relates to a functional part for an interior of a motor vehicle with an ergonomically shaped external contour, at least in a handle area, and with a support area or resting area for a vehicle occupant.
A functional part of this general type in the form of a shift lever is known from German Patent Document DE 28 28 781 A1. The shift lever is located in a manner known of itself in the interior of a motor vehicle and has an ergonomically shaped handle area to increase gripping security for the vehicle occupant during gear-shifting movements. However, when the vehicle is operated by different persons of different sizes and especially with different hand sizes, the majority of these persons cannot use the ergonomically shaped handle, since it is adjusted for only one single specific hand size.
An object of the invention is to create a functional part of the type recited at the outset that is individually adjustable for different vehicle occupants.
This object is achieved according to preferred embodiments of the invention by virtue of the fact that the handle area, the support area, or the resting area are formed by a flexible molded element filled with an electro-rheologic fluid, to which an electrical circuit, operable from the interior, is connected for reducing and increasing the internal friction of the fluid. Electro-rheologic fluids have the property that their internal friction is increased or decreased, depending on the type of fluid, when an electrical voltage is applied. As a result, a vehicle occupant can modify and form the shape of the handle area of a shift lever, an operating lever, a shift knob or rotary knob, or a steering wheel within certain limits in an individual manner, with the shaped element freezing in the selected form after the electrical voltage is removed when the electro-rheologic fluid with an inverse effect is used. Similarly, the supporting or resting areas of armrests and seats in vehicle interiors as well as headrests can be adapted individually. The solutions according to the invention therefore make it possible to provide individually adjustable shape operating elements, supporting and resting parts of vehicle seats, and portions of vehicle interior trim, so that both the operating comfort and the aesthetic design of the corresponding functional parts of the vehicle interior can be changed in suitable fashion.
In one embodiment of the invention, the flexible shaped element is formed by a plastic sheath provided with a closed cavity to receive the electro-rheologic fluid. This is an especially simple yet functionally reliable design.
In another embodiment of the invention, the flexible shaped element has a deformability that is restricted to certain contours. The limitation of deformability has the advantage that the functional reliability of the functional part cannot be adversely affected by the individual shape of the corresponding areas of its external contour.
In another embodiment of the invention, reduction of internal friction can be triggered by an impact sensor integrated into the vehicle and connected to the electrical circuit. As a result, the shaped element filled with electro-rheologic fluid also serves as an impact-energy-absorbing element, since impact energy can be absorbed when the shaped element is in the flexible state. Consequently, the risk of injury to occupants is reduced by a corresponding functional part in the shape of an operating element, a part of the interior trim, or other suitably designed parts.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.